PRIOR CONCURRENT THERAPY: Biologic therapy: No prior interferon No prior thalidomide for KS At least 6 months since prior suramin Chemotherapy: At least 4 weeks since prior chemotherapy Endocrine therapy: No prior systemic steroids except physiologic replacement doses of corticosteroids, sex hormones, or noncorticosteroids such as anabolic steroids for wasting syndrome Concurrent short-term courses of steroids allowed Radiotherapy: No prior radiotherapy Surgery: Not specified Other: At least 2 weeks since prior antiretroviral therapy OR On stable doses of 1 or more of the following for at least 2 weeks before study: Zidovudine, zalcitabine, didanosine, lamivudine, or stavudine Protease inhibitor Non-nucleoside reverse transcriptase inhibitor No other prior systemic anti-KS agent or regimen No other concurrent anti-KS therapy during the first 6 months of the study No concurrent sedating drugs that cannot be reduced to below a minimal level, sedating recreational drugs, or alcohol No change, initiation, or discontinuation of antiretroviral therapy unless medically indicated Concurrent intralesional therapy after 6 months on study on rare occasions for occasional painful or disfiguring lesions allowed